1. Field of the Invention
The present invention relates to a headrest for use in a vehicle or automobile, and is particularly directed to such a headrest that is formed by a foaming process by placing a generally "M"-shaped headrest frame with two stay portions within a trim cover assembly, then injecting a liquid foaming base material into the trim cover assembly, and curing the foaming base material together with the headrest frame and trim cover assembly integrally, thereby providing a headrest with two stays which can be used on a vehicle seat.
2. Description of Prior Arts
For example, the Japanese Laid-Open U.M. Publication No. 59-139157 discloses the foregoing kind of headrest having a generally "M" shaped headrest frame. According thereto, such headrest frame has a pair of stay portions which are projected outwardly from a trim cover assembly forming a part of headrest body. The generally "M" shape of headrest frame is advantageous in eliminating the need to provide a reinforcing rod between two lateral frame sections of the headrest frame in view of the "M" shaped part serving as the reinforcing rod, and also advantageous in permitting easy insertion of the headrest frame itself into within the trim cover assembly.
However, this sort of headrest has been found defective in that it is necessary to form a large opening in the trim cover assembly, which is so sufficient to allow the whole "M" shaped headrest frame to be inserted therethrough into within the trim cover assembly, and that, due to such large opening, during a foaming process, a liquid foaming base material will be leaked from the opening, which results in impairing an aesthetic outer appearance of headrest.